Ignition mechanism



Feb. 24, 1925. F 1,527,634 a. DICK IGNI TION IEGHANISI Filed oct. 22, 192s l s gg Patented Feb. 24, 1925.

UNITED STATES PATENT OFFICE.

VBURNS DICK, OF ST. LOUIS, MISSOURI, ASSIGNOR TO WAGNER ELECTRIC CORPORA- TION, OF ST. LOUIS, MISSOURI, A CORPORATION OF DELAWARE.

IGNITION IVIECHANISM'.l

Application filed October 22, 1923. Serial No. 669,906.

[ all whom t may comem:

Be it known that I, BURNS DICK, a subject of the King of Great Britain, residing at the city of St. Louis, State of Missouri,

United States of America, have invented a certain new and useful Ignition Mechanism, of which the following is such a full, clear, and exact description as will enable anyone skilled in the art to which it appertains to make and use the same, reference being had to the accompanying drawings, forming part of this speciication. l

My invention relates to ignition timing mechanism for internal combustion engines, its object being to provide a device for this purpose in which the circuit breaker arm is positively actuated in both its opening and closing movements. The invention is particularly suitable for use in battery ignition systems having a normally closed primary ignition circuit and has the advantages ot improving engine operation at both low and high speeds and increasing the life of the breaker contacts.

In the accompanying drawings Figure 1 is a cross-sectional view of a combined ignition timer and distributor in which my invention is embodied; Figure 2 is a plan view of the circuit breaker mechanism; and Figure 3 is a front view of the mountings 'for the breaker' arm, breaker contact and the actuating members which connect the breaker arm with the actuating cam.

The main supporting casting 1 for the timer distributor mechanism is of the form to enter a standard S. A. E. mounting sleeve on the lighting generator of an automobile. The operating shaft 2 extends through this support and is provided at its lower en'd with a coupling 20, by means of which it is connected to be driven by the engine. This operating shaft 2 carries a cam 3 for actuating the circuit breaker and also the distributor arm 4 mounted on the insulating disc 5. Thisl distributor' arm contacts with the high tension terminals in the usual manner. The distributor mechanism forms no part of my invention and being of a well known type will not be further described.

The mounting plate 6 is carried on the support and is capable of limited circumferential movement for timing adjustment by actuation of the arm 7, this movement being permitted by the elongated slots 8 through which the retainer bolts 9 pass. The breaker mechanism is carried on this mounting plate 6 and comprises a casting 10 riveted to the plate and provided with horizontally extending passages 11, which form supporting and guiding means for strips of fiber or other suitable material 12 and 13, by means of which the cam 3 may actuate the breaker arm let. This breaker arm is mounted on pivot 15 and at one end carries contact 16 adapted to cooperate with contact 17 carried on the casting 10. The pivot 15 is carried by a base member 19, suitably insulated from the plate 6 so that the primary ignition circuit 70 is opened and closed by means of the contact 16 and 17.

It will be noted that the ber strips 12 and 13 are adapted to contact with breaker arm 14: on opposite sides of the pivot 15, 75 with the result that when a high point of the cam passes the end of the strip 12, the breaker arm will be actuated in the direction to separate the contacts 16 and 17, and when said high point, in the further ro tation of the cam, contacts with strip 13, the arm will be actuated in the direction to close said contacts. The inner ends of strips 12 and 13 are so located that positive actuation of the breaker arm toward closed position is begun immediately after the opening movement of the arm has been completed, and except for very small clearance the arm is forced to closed position by the strip 13. The spring 18, interposed between one end of the arm and the block 10, from which it is insulated by the bushing 20, completes the closing operation and holds the contacts closed until they are again separated by the succeeding high point of the cam engaging with the strip 12. Since the chief function of this spring is to hold the contacts closed, it can be very much lighter than if the positive arm-closing means were omitted, with the result that the 100 life of the contacts will be increased, and that there is less pressure to overcome to initiate the opening movement of the breaker arm.

The fiber strips 12 and 13 are adapted to slide freely in the passages 11 and are not mechanically connected to the breaker arm 14 and do not add to the inertia of the arm.

Since. the motion of the breaker `arm in both directions is governed by the .motion of the cam, the time of separation of the 'contacts can vbe definitely oontrolledalld is proportional to the speed of the engine. This results iii an improvement lin operation of the ignition mechanism at high speeds since in breakers depending upon Va spring for their return to closed position, inertia 'causes theac-tual duration of closed circuit to beflessrthan yit -itivere governed solely by the number of vinterruptions per' unit of time. l

Having fully described my invention, what I claim as new and desire to secure by Letters Patent of the United `States is :V

In ignition mechanism for interiial combustion engines, the combination of a circuit breaker, an engine driven cam, two

`movable members interposed between the cam and circuitbreaker but not connected to the breaker, one of said members being adapted to impel the circuit breaker in one Y vdirection aiidzthefother in the opposite direcfset my hand and aiXe-d my seal.

BURNS Dion. 

